Technical Field
This invention relates to an acid based antifreeze formulation for inhibition and prevention erosion and corrosion of aluminum and the corrosion of other metals exposed to an aqueous liquid in automotive coolant systems. The formulation further inhibits mineral scale. Traditionally antifreeze/coolant is sold at nearly one-hundred percent glycol content. This concentrated packaging allows for flexibility so that the user can dilute the antifreeze/coolant, as needed, with available water to obtain the required freeze/boil protection. However, corrosion protection is needed over the entire dilution range.
In modern automotive engineering, many engine components are fabricated from aluminum. Engine coolants, primarily ethylene glycol or propylene glycol based solutions, must transfer heat from operating aluminum engines while inhibiting corrosion. Older automotive engines did not have aluminum components and thus, the traditional antifreeze/coolant compositions may produce corrosion in heat rejecting aluminum or aluminum alloy components. The cavitation erosion-corrosion of aluminum water pumps upon exposure to aqueous systems such as water-cooled internal combustion engine coolants is a relatively new development.